[coreboot] log2c, log2f and fms

[Carl-Daniel Hailfinger]

Hi,

unless I'm mistaken, the fms() function is equivalent to log2f(), but
the former is in asm while the latter is in C.

Generally, I'd like to have a libmath.c with all these mathematical
functions. Having a file only for log2 variants is not exactly the most
optimal tree organization.

How do we treat functions which have an optimized asm version but also
exist as C code?
- Weak functions?
- Macro tricks like #ifdef _HAVE_ARCH_LOG2C ?
- Kill the optimized asm completely?

Regards,
Carl-Daniel